U.S. patent number 6,940,016 [Application Number 10/635,126] was granted by the patent office on 2005-09-06 for electrical rough-in box for low voltage transformer.
This patent grant is currently assigned to Desa IP, LLC. Invention is credited to Roger Dennis Cornett, Douglas Dean Rohrer, Scott Blaise Tylicki.
United States Patent |
6,940,016 |
Cornett , et al. |
September 6, 2005 |
Electrical rough-in box for low voltage transformer
Abstract
An electrical rough-in box for a low voltage transformer is
provided. The box has a removable cover with a low voltage
transformer mounted there through. The removable cover contains a
recessed portion for accommodating low voltage wiring. A sidewall
of the box contains a channel for low voltage wiring, thus
permitting flush mounting of the box against a wall stud.
Inventors: |
Cornett; Roger Dennis (Bowling
Green, KY), Tylicki; Scott Blaise (Bowling Green, KY),
Rohrer; Douglas Dean (Bowling Green, KY) |
Assignee: |
Desa IP, LLC (Bowling Green,
KY)
|
Family
ID: |
34135572 |
Appl.
No.: |
10/635,126 |
Filed: |
August 6, 2003 |
Current U.S.
Class: |
174/58; 174/50;
174/60; 439/535 |
Current CPC
Class: |
H01F
27/06 (20130101); H02G 3/126 (20130101); H01F
27/04 (20130101) |
Current International
Class: |
H01F
27/04 (20060101); H01F 27/02 (20060101); H01H
9/02 (20060101); H01H 009/02 () |
Field of
Search: |
;174/58,60,50,135
;220/3.2,3.3,402 ;248/906 ;439/535 |
References Cited
[Referenced By]
U.S. Patent Documents
Primary Examiner: Patel; Dhiru R.
Attorney, Agent or Firm: Middleton & Reutlinger
Claims
We claim:
1. An electrical rough-in box for a low voltage transformer,
comprising: a rough in box comprising one or more sidewalls and a
bottom wall, wherein said one or more sidewalls are connected to
said bottom wall and have a channel recessed therein; a cover
removably attached to said rough in box, forming a high voltage
wiring section of about 120V AC in said rough in box, said cover
comprising a recessed portion adjacent to one or more flanges
forming a raised relief in relation to said recessed portion to
form a low voltage wiring section of about 24 Volts or less AC or
DC and said flanges contain an entryway aligned with said channel,
wherein said one or more flanges are adapted to accept means for
attaching said cover to said rough in box, said recessed portion
having an opening there through; a low voltage transformer
comprising a primary high voltage end and a secondary low voltage
end, wherein said low voltage transformer is attached to said
cover, and said secondary low voltage end of said low voltage
transformer is disposed through said opening in said recessed
portion of said cover into said low voltage wiring section; a first
plurality of wires affixed to a high voltage source and extending
from the exterior of said rough in box through an entryway in said
rough in box into said high voltage wiring section and connecting
to said primary high voltage end of said low voltage transformer;
and a second plurality of wires connected to said secondary low
voltage end of said low voltage transformer for attachment to a low
voltage appliance at about 24 Volts or less AC or DC.
2. The electrical rough-in box of claim 1, wherein said low voltage
transformer is removably attached to said cover.
3. The electrical rough-in box of claim 2, further comprising one
or more brackets for removably attaching said low voltage
transformer to said cover.
4. The electrical rough-in box of claim 1, further comprises a
means for attaching said rough in box to a wall stud.
5. The electrical rough-in box of claim 1 wherein said rough in box
is unitary.
6. An electrical rough-in box for a low voltage transformer,
comprising: a square electrical rough in box having a removable
cover, a bottom wall and a plurality of side walls, any of said
walls having a formed wireway for allowing passage of at least one
low voltage wire; said removable cover removably attached to said
rough in box forming a high voltage wiring section interior of said
rough in box, said removable cover affixed to said rough in box,
said removable cover having an opening there through and having a
flange on a periphery contacting said rough-in box, said flange
having a wire passageway aligned with said formed wireway of said
rough in box; a low voltage transformer having a primary high
voltage end and a secondary low voltage end, wherein said low
voltage transformer is disposed through said opening of said
removable cover, said secondary low voltage end of said low voltage
transformer being disposed through said opening in said cover and
facing outward from said removable cover thereby forming a low
voltage wiring area for electrical connection of a plurality of low
voltage wires to said secondary low voltage end of said low voltage
transformer; a plurality of high voltage wires affixed to a high
voltage source and extending from the exterior of said rough in box
through a entryway in said rough in box into said high voltage
wiring section and connecting to said primary high voltage end of
said low voltage transformer; said plurality of low voltage wires
electrically connecting said secondary low voltage end of said low
voltage transformer to a low voltage appliance.
Description
FIELD OF THE INVENTION
The present invention relates generally to an electrical rough-in
box for a low voltage transformer. The rough-in box provides an
electrician with improved access to the transformer, terminals,
connectors and wiring inside of the box thus reducing the time and
cost for the installation of, for example, a door bell system. The
rough-in box also permits a push button switch, transformer and
chime mechanism associated with a door bell system to be located in
closer proximity to one another thus reducing the cost for
installation of such a system.
BACKGROUND OF THE INVENTION
Electrical power is usually provided to residential homes at a line
voltage of 120 volts AC by a public electrical utility. Inside of
the home, certain applications (such as halogen lighting fixtures)
require a reduction from the standard household current of 120
volts to the appropriate lighting requirements, generally 12 or 24
volts. This reduction, or step-down, in voltage is typically
accomplished by means of a low voltage electrical transformer.
Another type of household electrical application that requires the
use of a transformer is a door bell system. A door bell system
comprising one or more push button switches, electrical wiring and
a chime mechanism require a transformer to step down the standard
120 volt household current to a lower voltage which is appropriate
for the chime mechanism, often 16 volts. Currently, in many
building applications such as a residence, electricians must search
for appropriate locations to mount such low voltage transformers
before they begin to pull electrical wire to complete, in the case
of a door bell system, the electrical circuit between the push
button switch, the transformer and the chime mechanism. The
National Electric Code ("NEC") and local codes do not permit
transformers to be mounted in attics or non-accessible locations
such as inside of finished walls. As such, in many cases
transformers are mounted by electricians in a closet or other
location close to the chime mechanism where the transformer can be
hidden. This is often an inconvenience to the homeowner.
Alternatively, electricians mount the transformer directly to the
main electrical breaker box. This location, however, can require
significantly more electrical wire and electrician time to complete
the push button switch, transformer, chime mechanism electrical
circuit and hence be more costly.
Ideally, the push button switch, the chime mechanism, and the low
voltage transformer are all located in close proximity to each
other. In practice, it rarely works this way. Because the
transformer is usually mounted outside of the walls, it is located
in an out-of-the-way place so as not to be an eyesore. Conversely,
the chime mechanism must be mounted in an open place in the
residence so that it is likely to be heard by an occupant when the
push button is depressed. If mounted inside of a closet close to
the transformer, for example, the sounds created by the chime
mechanism might not be heard. As a result, wiring needs to be run
from the push button, which is necessarily mounted near an entrance
door, to the transformer, which is necessarily mounted in an
out-of-the-way place, to the chime mechanism, which is necessarily
mounted in a central area of the house where it can be heard. The
wiring is run inside of the walls beneath sheet rock. The
transformer and chime mechanism are mounted outside of the walls.
If there is a substantial delay between the time the wiring is
originally run and the time the chime mechanism and transformer are
mounted, it can be difficult for an electrician to find the
previously run wires that may have been covered by sheet rock. All
of this makes the installation of a door bell system more
complicated, time-consuming and expensive than is necessary.
SUMMARY OF THE INVENTION
The present invention is an electrical rough-in box for a low
voltage transformer which is designed not only to overcome these
problems but also to provide an electrician with improved access to
the transformer, terminals, connectors and wiring inside of the
rough-in box thus reducing the amount of an electrician's time, and
hence the cost, for many low voltage applications.
The area inside of the rough-in box is designated the line voltage
wiring section. Line voltage is standard household current of 120
volts AC. Line voltage wires can enter the interior of the box
through holes drilled by the electrician in the walls of the box
or, more preferably, through standard knock-outs in one or more
wall of the box. The box has a removable cover secured to the body
of the box by screws, bolts, clamps or other securing means.
Through the removable cover is mounted a typical low voltage
transformer such as a 16 volt AC used for hardwired doorbell
systems. The low voltage transformer has two ends: a line voltage
end and an opposed low voltage end. The outside wall of the cover
of the box has a recessed section that the low voltage end of the
transformer protrudes through. This recessed section is also the
low voltage wiring section. That is, wires connected to and leading
from the low voltage end of the low voltage transformer reside in
the low voltage wiring section. These low voltage wires may be
connected directly to, for example, a low voltage appliance such as
a chime mechanism or, via channel in a sidewall of the body of the
box and an entryway to the channel in a flange of the removable
cover, to an electrical switch such as a door bell push button.
The electrical rough-in box of the present invention would
typically be installed during the rough-in stage of the electrical
work in, for example, a residence. The line voltage wires carrying
a power supply to the rough-in box would come off of a nearby
branch circuit. The electrical rough-in box, with the low voltage
transformer protruding through the recessed section of the
removable cover and, preferably, mounted to the removable cover,
would be mounted to a wall stud in the same manner as a normal
electrical rough-in box. The line voltage and low voltage wire
connections to the transformer could then easily be made by an
electrician at either the rough-in stage or at the finish stage of
the electrical work simply by removing the cover of the box on
which the transformer is mounted and then accessing the appropriate
terminals or connectors. Wall insulation can be brought up next to
the box and during the drywall or wall finishing process an opening
to the cover of the box would be cut through the wall as is
normally done with electrical rough-in boxes. A chime mechanism
would preferably be mounted on the finished wall over the
electrical rough-in box. This arrangement would minimize the amount
of low voltage wiring which would need to be run between the
rough-in box and the chime, thus reducing the cost for
installation. Alternatively, the electrical rough-in box can be
mounted on a floor joist or a roof rafter with the low voltage
wiring run from that location to the chime mechanism and push
button switch.
In another embodiment of the invention, the low voltage transformer
protruding through the recessed portion of the removable cover is
mounted to the bottom wall of the electrical rough-in box instead
of to the removable cover.
In yet another embodiment of the invention, the low voltage
transformer protruding through the recessed portion of the
removable cover is mounted to a sidewall of the electrical rough-in
box instead of to the removable cover.
In accordance with the foregoing objects, an electrical rough-in
box for a low voltage transformer is disclosed providing improved
access to the transformer, terminals, connectors and wiring. The
electrical rough-in box of the present invention also permits a
push button switch, transformer and chime mechanism associated with
a door bell system to be located in close proximity to one another,
thus reducing the cost for installation of such a system.
The novel aspects of the invention are set forth with particularity
in the appended claims. The invention itself, together with further
objects, features, aspects and advantages will be readily apparent
to those skilled in the art and a better understanding of the
present invention may be had by reference to the following detailed
description taken in connection with the following drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a front perspective view of the electrical rough-in box
depicting the low voltage wires from the low voltage end of the low
voltage transformer connected to a door bell system chime mechanism
and further to a push button switch via a channel in a sidewall of
the box.
FIG. 2 is a partially exploded front perspective view of the
preferred embodiment of the electrical rough-in box.
FIG. 3 is an additional partially exploded front perspective view
of the preferred embodiment of the electrical rough-in box.
FIG. 4 is an exploded front perspective view of the preferred
embodiment of the electrical rough-in box with the low voltage
transformer mounted to the removable cover.
FIG. 5 is a cross-sectional view of the electrical rough-in box
along line 5--5 of FIG. 1, mounted to a wall stud, and with the low
voltage transformer mounted to the removable cover.
FIG. 6 is a top plan view of the electrical rough-in box along line
6--6 of FIG. 1, mounted to a wall stud.
FIG. 7 is a cross-sectional view of the electrical rough-in box,
along line 5--5 of FIG. 1, depicting the low voltage transformer
mounted to the bottom wall of the rough-in box.
FIG. 8 is a top plan view of the electrical rough-in box, along
line 6--6 of FIG. 1, depicting the low voltage transformer mounted
to the bottom wall of the rough-in box.
FIG. 9 is a cross-sectional view of the electrical rough-in box,
along line 5--5 of FIG. 1, depicting the low voltage transformer
mounted to a sidewall of the rough-in box.
FIG. 10 is a typical schematic wiring diagram.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
Referring now to the drawings there is shown in FIG. 1 an
electrical rough-in box for a low voltage transformer. The box 10
preferably includes a generally square-shaped cover 18 and
generally square-shaped body 12 having four sidewalls 14a, 14b,
14c, 14d and a bottom wall 16 (FIG. 2). The bottom wall 16 is in
contact with and connected to each of the sidewalls. It will be
understood by those of ordinary skill in the art that the shape of
the body 12 and cover 18 need not be generally square but may,
alternatively, be generally rectangular, triangular, circular or of
other geometric shape.
The box 10 may be constructed of metal or plastic. Preferably, the
box 10 is formed from moldable plastic, such as polycarbonate or
the like, which makes the box easy to manufacture using standard
injection molding techniques. Sidewalls 14a, 14b, 14c, 14d and
bottom wall 16 are preferably molded together to form a one piece
body 12. One or more of sidewalls 14a, 14b, 14c, 14d preferably
have a channel or wireway 15 recessed therein on their outside wall
for receiving a low voltage wire 40 (FIG. 1). Cover 18 is
separately molded and is removably attached to body 12 by screw 22,
bolts, clasps or other attaching means disposed through holes 20 in
the flanges 17 of the cover 18 (FIG. 2). The outside wall of cover
18 is molded to form a recessed portion 38 therein defining a low
voltage wiring section 42 (FIG. 6). The recessed portion 38 is
surrounded by flanges 17 which have a raised relief in relation to
the recessed portion 38. One or more of flanges 17 contain an
entryway or wire passageway 19 which is aligned with one or more of
channels 15 when the cover 18 is attached to the body 12 (FIG.
2).
Referring to FIG. 4, a low voltage transformer 24 having a line
voltage end or primary side and a low voltage end or secondary side
is disposed through an opening 26 in the recessed portion 38 of the
cover 18. The transformer 24 is preferably mounted to cover 18
through opening 26 in cover 18 by means of brackets 44 and screws
46 disposed through holes 48 in the brackets; the screws 46 being
in a securing relationship with posts 50 which are integrally
molded with and attached to cover 18. One or more mounting tabs 28
are integrally molded with and attached to one or more of the side
walls 14 of body 12 which allows the electrical rough-in box 10 to
be fastened to a stud 52 in a wall or other fixed structure. The
mounting tabs 28 will preferably have notches or holes therein 30
to accommodate a stud fastening means such as nails, bolts or
screws (not shown).
In another embodiment of the invention (see FIGS. 7 and 8), the low
voltage transformer 24 instead of being mounted to cover 18 is
mounted to bottom wall 16 of body 12 by securing means such as
screws, bolts, clasps, brackets 58, straps or other molded
features. In this embodiment the low voltage end of transformer 24
is still disposed through opening 26 in the recessed portion 38 of
cover 18.
In yet another embodiment of the invention (see FIG. 9), the low
voltage transformer 24 instead of being mounted to cover 18 is
mounted to a sidewall 14 of body 12 by securing means such as
screws 60, bolts, clasps, brackets, straps or other molded
features. In this embodiment the low voltage end of transformer 24
is still disposed through opening 26 in the recessed portion 38 of
cover 18.
Referring to FIG. 5, the area inside of the box 10, defined by the
body 12 and the cover 18 secured to the body 12, is designated the
line voltage wiring section 32. The line voltage end of transformer
24 is contained within the line voltage wiring section 32. The low
voltage end of transformer 24 protrudes through cover 18, by means
of an opening 26 in the cover, and into the low voltage wiring
section defined by the recessed portion 38 of cover 18. The
removable cover thus serves to separate the low voltage wiring
section 42 outside of box 10 from the line voltage wiring section
32 inside of box 10.
Line voltage wires 34 carrying standard household current of 120
volts enter the line voltage wiring section 32 through holes
drilled by the electrician in any of sidewalls 14 or bottom wall 16
of body 12 or, more preferably, through any of knockout areas or
entryway 36 which can be easily removed in order to form openings
for the line voltage wires 34. The knockout areas or preformed
apertures 36 are located in the sidewalls 14 and/or the bottom wall
16 of the body 12 (see FIG. 3). The line voltage wires 34 carrying
a standard household current of 120 volts are connected to the line
voltage end of transformer 24 within the line voltage wiring
section 32 of box 10 (FIG. 5). The low voltage transformer
steps-down or reduces the line voltage current to a lower voltage
current suitable for transmission to, for example, household
electrical lighting applications or a door bell system. Referring
to FIG. 1, in the case of a doorbell system the reduced voltage
current is carried by low voltage wires 40 in the low voltage
wiring section 42 of cover 18 directly to a low voltage appliance
(door bell chime 54), as well as to push button switch 21 by means
of an entryway 19 in a flange 17 of cover 18 which leads into the
recessed channels 15 in a sidewall 14 of box 10.
As can be observed in FIG. 6 which illustrates the box 10 secured
to a wall stud 52 and drywall 56 installation having been
completed, the advantage provided by channel 15 over prior art
electrical rough-in boxes is that because the channel is recessed,
it can accommodate the low voltage wires 40 therein, thus allowing
the sidewall 14 of box 10 to be easily mounted flush against wall
stud 52.
A distinct advantage of the electrical rough-in box 10 of the
present invention over prior art electrical rough-in boxes is that
because the cover 18 is easily removable from body 12, and the
transformer 24 is easily removable from the cover 18, both by means
of loosening screws 22 and 46, respectively, an electrician is
afforded improved access not only to the transformer 24 but also to
the terminals, connectors and wiring within box 10. This provides a
significant advance over the prior art in terms of the convenience
of use, construction and design for an electrician installing an
electrical rough-in box for a low voltage transformer. FIG. 10
illustrates a typical wiring diagram as easily understood by those
skilled in the art.
In this manner an electrical rough-in box for a low voltage
transformer is provided which readily avoids the problems and
shortcomings associated with prior art electrical rough-in
boxes.
The preferred embodiment has been illustrated and described.
Further modifications and improvements may be made thereto as may
occur to those skilled in the art and all such changes as fall
within the true spirit and scope of this invention are to be
included within the scope of the claims to follow.
* * * * *